Means for unblocking lenses



y 7, 9 G. w. JACKSON 2,399,679

' MEANS FOR UNBLOCKING LENSES Filed May 20, 1943 22 35 3/ s I 36 i I 30 38 37 A \-4-2/ 5 M 9,

TIM: 4 3222* 5 7 z v I MINVENTOI-T .GEO/EGE w. JACKSON BY 5/ 0M 111%RNEY terval while on the Patented May 7, 1946 George W. Jackson,

Southbrldge, Mass, assignmto American Optical Company, Southbridge, Masa, a voluntary association of Massachusetts Application May 20, 1943, Serial No. 487,824 12 Claims. (Cl. 62-1) This invention relates to devices for removing articles from supporting means and more particularly relates to novel means for removing a lens from a support to which the lens has been initially adhesively secured.

One of the principal objects of the invention is to provide improved means for removing a lens from a holder sively secured by introducing a relatively marked difierence in coeflicient of expansion between the lens and the adhesive through rapid chilling of the lens whereby the lens will become dislodged from the holder.

Another object is to rapidly chill pitch blocked lenses for an automatically controlled time inblock whereby the lens is caused to contract more rapidly than the pitch and will thereby become dislodged from the block.

Another object is to provide simple, emcient and economical means for accomplishing the above result.

Another object is to provide means embodying the use of carbon dioxide for chilling the lens whereby the extent of exposure of the blocked lens to the carbon dioxide may be positively controlled.

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawing and it will be apparent that many changes may be made in the details of construction, arrangement of parts shown and described without departing from the spirit of the invention as expressed in the accompanying claims. I, therefore, do not wish to be limited to the exact details of construction, arrangement of parts shown and described as the preferred form only has been given by way of illustration.

Referring to the drawing:

Fig. l is a. side elevational view of the device embodying the invention; and y Fig. 2 is a longitudinal sectional view taken as on line 2-4 of Fig. 1 and looking in the direction indicated by the arrows.

The broad idea of removing a lens which has been secured to a block or holder by means of an adhesive, such as pitch, by chilling the lens more rapidly than the pitch to cause the lens to snap loose from the block or holder is not new in the art. Several different arrangements have been devised in the past to utilize liquid COz-as the chilling means. One of the main difllculties with most known prior art devices utilizing liquid 00: has been in controlling the amount of said CO: used in the actual chilling operation. In

to which it has been adhemost instances liquid C0: is obtained from a tank supply and, as used in the past, great diiflculty was encountered in obtaining the most economical use of the supply.

The present invention, more particularly to the therefore is directed provision of means whereby the greatest possible number of removals parts throughout the several views 7 adapted tobe positioned for the ballle 19. There is can be obtained from a single source of supply and thereby greatly reducing the cost of unblocking lenses through the use of such chilling material.

Referring more particularly to the drawing wherein like characters of reference designate like the device embodying the invention comprises a main support 4 carrying an upright bearing member 5 in which a bar member 8 is slidably supported. The bar member 6 is provided adjacent the upper end thereof with a holder 1 for supporting the lens block 8 to which a lens 8 has been adhesively secured as by a layer of pitch or other suitable adhesive l0. Thesaid bar 8 is providedadiacent the lower end thereof with hand or foot engagement means II by which the'bar member, together with the holder I andlens block 8, may be moved in a downward direction. A coil spring I: surrounding the bar member 8 is adapted to engage the upper surface It of the bearing and the under surface l4 of the support 1 to constantly urge said bar member 8 in an upward direction. The extent of said movement is controlled by stop means l5 engaging the lower end of the bearing 5 or other suitable stop means. The engaging surfaces of the member 5 and the stop means l5 are provided with a facing ii of resilient material functioning as cushioning means. The support 4 also carries a housing or hood II which is adapted to form a hollow chamber IS in which the lens block 8 having the lens 9 adhesively secured thereto is chilling treatment. Adjacent the holder 1 there is supported a flange member is functioning as bame means disposed adjacent the lower end of the hood l1 with the diameter of said baflle means being smaller than the diameter of the hood to provide an exhaust space 20 circumferentially of the also carried by the support 4 a valve member 2| having a central tubular portion 22 provided with threaded coupling means 23 to which a pipe or hose line 24 leading to a source of supply of'liquidCOz may be connected. The tubular member 22 has a flanged end 25 clamped between the upper portion of the support 4 and a peripheral flange 20. formed inteportion oi which forms a valve seat for a valve needle or contact member 20 carried by a plunger 30 slidably supported internally of the tubular member 22. The plunger member 80 is normally urged in a downward direction by means of a coil spring or the like 3| which engages the upper portion 'of the plunger adjacent one end thereof and which engages a shouldered edge 32 internally of the tubular member 22. The said plunger has a plurality of longitudinal grooves 32 therein through which liquid, passing through the restricted opening 34 in the coupling means adjacent the upper end of the tubular member 22. may pass to gain access to the needle valve 28 and restricted opening 28. The tubular member 22 is preferably formed of brass or other nonmagnetic material. The plunger 30, while functioning as means for supporting the needle valve 28, actually is the core of an iron clad solenoid having a plurality of windings l5 encased in an iron casing 36. The windings I! are connected through suitable lead wires 31 and control switch 29. The time control switch may be oi any known commercial type which when operated will energize the solenoid for a predetermined controlled time interval and which may be varied for any desirable duration of energizing of the coil 25 of the solenoid.

The function of the device is substantially as follows:

The plunger 20 is normally urged in a downward direction by the coil spring}! causin the needle valve 29 to be relatively firmly seated on the valve seat of the restricted opening 28. This shuts oil the flow of liquid C02 through said restricted opening. The engagement means II is then engaged to force the bar-like member 8 in a downward direction to move the holder 1 outwardly of the chamber IS an amount sufl'icient to permit the lens holder or block 8 h'aving a lens secured thereto by a layer of pitch or other suitable adhesive III to be placed on said holder. Holders of this nature have a shank portion 4| 1 thereon which is adapted to extend inwardly of the holder 1, which holder in this particular instance, is in the form of a cylinder having an upper supporting edge and a, hollow center to' receive the shank ll holding portion of the block 8 to rest on the upper edge of the cylinder.

thereby permitting the main Pressure is then released on the member II to allow th'e holder and block 8 to move upwardly into the chamber It, The

time control switch 39 is then operated to cause a current flow for a-Dredetermined duration to be directed to the solenoid coil 3!. This causes the magnetic field of the coil 35 to raise the core or plunger I0 against the action of the coil spring 31. This causes the needle valve 29 to he raised relative to the valve seat of the restricted opening 28 thereby permitting the liquid CO: to be.

discharged through said restricted opening. The discharge is in the form of a spray which enntoatimethe holder and a new placed thereon.

The solenoid operating through the time control switch causes the needle valve 29 to be raised relative to the valve seat of the restricted opening 28 for a controlled time interval and the said time control switch willfunction automatically to shut oil the current flow to the solenoid coil whereupon the plunger or core 30 will be automatically forced downwardly by the spring II to close the restricted opening 28. This provides a positive control for the amount of ilow of the liquid 00: through the restricted opening 28 and prevents excessive and unrequired usage of said liquid C02.

The construction set forth above is relatively simple and inexpensive in nature and obviates the use of seals, packings and the like which were required with most known prior art constructions. This is particularly of advantage when working at the extremely high pressures of the magnitude of. 800 to 1000 lbs. required with the use of liquid CO2.

From the foregoing description it will be seen that simple, e'ilicient and economical means and methods haveibeen provided for accomplishing all of the dbiects and advantages of the invention.

Having described my invention, I claim:

1. In a device of the character described the combination of a support, a housing carried by said support, a holder member on said support having a portion movable into and out of the housing, a member having a passageway with a restricted opening therein leading into the housing, a plunger in said passageway, said plunger having a contact portion carried by the end thereof for engaging the walls of the restricted opening, said plunger constituting the core of a solenoid, a solenoid coil surrounding said member having the passageway therein and said plunger in the last mentioned passageway, means for normally-urging said plunger and the contact portion carried thereby toward the restricted opening to close said opening, a source of liquid refrigerant connected with said passageway and means for energizing the solenoid for a controlled period of time-for causing said plunger to move in a direction opposite the direction of the force exerted by the means for urging said contact portion into engagement with the walls of the restricted opening whereby a controlled amount of liquid refrigerant will be permitted to flow through said restricted opening into the housing.

2. In a device of the character described the combination of a support, a housing carried by said support, a holder member on said support lens and block assembly having a portion movable into and out of the gages the upper surface of the lens substantially throughout the entire area of said upper surface and thereby suddenly chills the lens causing it to contract more rapidly than the contraction of the pitch or other adhesive I 0 whereupon the lens will map loose from said adhesive. The member H is then engaged to move the bar-like member 6 in a downward direction whereupon the block and loosened lens may be removed from housing, a member having a passageway with a restricted opening therein leading into the housin a plunger in said passageway, said plunger having a contact portion carried by the end thereof for engaging the walls of the restricted opening, said plunger constituting the core of a solenoid, .a solenoid coil surrounding said member having a passageway therein and said plunger in the last mentioned passageway, means for normally urging said plunger and the contact portion carried thereby toward the restricted opening to close said opening, a source of liquid refrigerant connected with said passageway, means for energizing the solenoid and time control switch means for controlling the period of time'oi said energizing for causing said plunger to move in a direction opposite the direction of the force exerted by the means for urging said contact nortion into engagement with the walls of the restricted opening whereby a controlled amount of liquid refrigerant will be permitted to flow through said restricted opening into the housing.

3. In a device of the character described the combination of a support, a housing on said support, a bearing member carried by said support, a bar-like member slidably supported in said bearing member having a holder member at an end thereof presented toward the housing, re-

silient means associated with said bar-like member for'norxnally urging said holder member toward the housing and for permitting said holder member to be movedout of the housing, a member having a passageway with a restricted opening leading into the housing in substantial alignment with the holder, 9. plunger-in said passageway having grooves longitudinally thereof, said plunger having a contact portion carried by the end thereof for engaging the walls of the restricted opening, resilient means in said passageway for normally urging the plunger toward the restricted opening and the contact portion into seated relation with the walls of the said opening, a solenoid coil surrounding said member having the passageway therein, a source of liquid refrigerant connected with said passageway and means for energizingthe solenoid to cause the plunger to be moved in a direction opposite the direction of the force exerted by the resilient means to disengage the contact portion from the walls of the restricted opening to permit the liquid refrigerant to flow through the longitudinal grooves in the plungerand through the restricted opening into the housing.

4. In a device of the character described the combination of a support, a housing on said support, a bearing member carried by said support, a bar-like member slidably supported in said bearing member having a holder member at an end thereof presented toward the housing, resilient means associated with said bar-like member for normally urging said holder member toward the housing and for permitting said holder member to be moved outwardly of the housing, a member having a passageway with a restricted opening leading into the housing in substantial alignment with the holder, a plunger in said passageway having grooves longitudinally thereof, said plunger having a contact portion carried by the end thereof for engaging the walls of the restricted opening, resilient means in said passageway for normally urging the plunger toward the restricted opening and the contact portion into seated relation with the walls of the 55 said opening, a solenoid coil surrounding said member having the passageway therein, a source of liquid refrigerant connected with said passageway, means for energizing the solenoid, and

time controlled switch means for controlling the o a period of energizing of the solenoid to cause the plunger to be moved in a direction opposite the direction of the force exerted by'the resilient means to disengage the contact portion from the walls of the restricted opening to permit the liq- 85 uid refrigerant to flow through the longitudinal grooves in the plunger and through the restricted opening into the housing.

5. In a device of the character described the combination of a support, a housing on said sup- 70 port, a bearing member carried by said support, a bar-like member slidably supported in: said bearing member having a holder member at an end thereof presented toward the housing, resilient means associaud ber for normally urging said holder member toward the housing and for permitting said holder to be moved outwardly of the housing, a member having a passageway with a restricted opening leading into the housing in substantial alignment with the holder, a plunger in said passageway having grooves longitudinally thereof, said plunger having a contact portion carried by the end thereof for engaging the walls of the restricted opening, resilient means in said passageway for normally urging the plunger toward the restricted opening and the contact portion into seated relation with the walls of the said opening, a solenoid coil surrounding said member having the passageway therein, a source of liquid refrigerant connected with said passageway, means for energizing the solenoid to cause the plunger to be moved in a direction opposite the direction of the force exerted by the resilient means to disengage the contact portion from the walls of the restricted opening to permit the liquid refrigerant to flow through the longitudinal grooves in the plunger and through the restricted opening into the housing and an engagement member carried by the bar-like member for moving said bar-like member against with said bar-like mem- II the action of the resilient means which normally urges the holder member carried by said bar member towards the housing.

6. In a device of the character described the combination of a support, a housing on said support, a bearing member carried by said support, a bar-like member slidably supported in said bearing member having a holder member at an end thereof presented toward the housing, resilient means associated with said bar-like member for, normally urging said holder member toward the housing and for permitting said holder member to be moved outwardly of the housing, a member having a passageway with a restricted opening leading into the housing in substantial alignment with the holder, a plunger in said passageway having grooves longitudinally thereof, said plunger having a contact portion carried by the end thereof for engaging the walls of the restricted opening, resilient means in said passageway for normally urging the plunger toward the restricted opening and the contact portion into seated relation with the walls of the said opening, a solenoid coil surrounding said member having the passageway therein, a source of liquid refrigerant connected with said passageway, means for energizing the solenoid, time control switch means for controlling the period of energizing of the solenoid to cause the plunger to be moved in a direction opposite the direction of the force exerted by the resilient means to disengage the contact portion-from the walls of the restricted opening to permit the liquid refrigerant to flow through the longitudinal grooves in the plunger and through therestricted opening into the housing and an engagement member carried by the bar-like member for moving said bar-like member against the action of the resilient means which normally urges the holder member carried by said bar member towards the housing.

7. In a device of the character described the combination of a support, a housing on said support, a bearing member carried by said support, a bar-lik member slidably supported in said bearing member having a holder member at an end thereof presented toward the housing, resilient means associated with said bar-like member for normally urging said holder member toward the housing and for permitting said holder member to be moved out of the housing, a member having a passageway with a restricted opening leading into the housing in substantial alignment with the holder, a plunger in said passageway having rooves longitudinally thereof, said plunger having a contact portion carried by the end thereof for engaging th walls of the restricted opening, resilient means in said passageway for normally urging th plunger toward the restricted opening and the contact portion into seated relation with the walls of the said opening, a solenoid coil surrounding said member having the passageway therein, a source of liquid refrigerant connected with said passageway, means for energizing the solenoid and variable time control switch means connected with said solenoid for controlling the time interval of energizing of said solenoid.

8. In a device of the character described the combination of a housing having means associated therewith movable to a position internally thereof for supporting a holder having a lens adhesively secured thereto, a passageway leading into said housing, a member having a restricted opening therein aligned with said passageway adjacent the end thereof connecting with the housing, a source of liquid CO2, means for connecting said source of liquid CO: to the passageway, a plunger in said passageway having an end portion adapted to engage the member having the restricted opening therein and to overlie said opening and means having automatic time control means associated therewith and cooperative- 1y related with the plunger for moving said plunger away from said member having the restricted opening therein for a controlled period of time for regulating the extent of flow of liquid CO: through said restricted opening into said housing.

9. In a device of the character described the combination of a support, a housing carried by said support, bearing means carried by said support, a bar member slidably supported in said bearing means and having a holder at an end thereof presented toward the housing, resilient means normally urging said bar member and holder in a direction towards the housing to support said holder inwardly of said housing, a passageway leading into said housing having a portion with a restricted opening therein, a plunger member in the passageway having a portion of a diameter smaller than the diameter of the passageway and having an end portion for engaging the portion having the restricted opening therein in overlying relation with the opening, means for normally urging said plunger member towards the portion having the restricted opening therein, a refrigerant conduit connected with said passageway, the flow of refrigerant between the portion of the plunger of smaller diameter and the wall of the passageway and through said restricted opening being limited by the overlying relation of the end of the plunger with the restricted opening, and electro-magnetic means cooperatively functioning with said plunger memher for urging said plunger member in a direction away from the portion having the restricted opening therein to permit the flow of the refrigerant through said restricted opening.

10. In a device of the character described the combination of a support, a housing carried by said support, bearing means carried by said support, a bar member slidably supported in said bearing means and having a holder at an end thereof presented toward the housing, resilient means normally urging said bar member and holder in a direction towards the housing to support said holder inwardly of said housing, a passageway leading into said housing having a portion with a restricted opening therein, a plunger member in the passageway having a portion of a diameter smaller than the diameter of the passageway and having an end portion for engaging the portion having the restricted opening therein in overlying relation with the opening, means for normally urging said plunger member towards the portion having the restricted opening therein, a refrigerant conduit connected with said passageway, the flow of refrigerant between the portion of the plunger of smaller diameter and the wall of the passageway and through said restricted opening being limited by the overlying relation of the end of the plunger with the restricted opening, electro-magnetic means cooperatively functioning with said plunger memher for urging said plunger member in a direction away from the portion having the restricted opening therein to permit the flow of the refrigerant through said restricted opening, and a time control switch connected with said electro-magnetic means for controlling the time interval of energizing the said electro-magnetic means.

11. In a device of the character described, the combination of a housing, means for supporting a holder having work adhesively secured thereto in said housing, a member having a passageway therein connected with the housing, with said passageway leading into said housing, a liquid refrigerant conduit connected with said member having the passageway therein, valve means in said passageway for closing said passageway and electrically operated means for retaining said valve means open for a controlled predetermined time interval.

12. In a device of the character described, the combination of a housing, means for supporting a holder having work adhesively secured thereto in said housing, said housing having an opening therein, a member secured to said housing having a passageway aligned with said opening, means in said passageway having a portion for engaging said opening to close the same, a liquid refrigerant conduit connected with said member having the passageway therein and electrically operated means for inducing a force on said means having the portion for closing said opening in a direction away from said opening for a predetermined time interval for permitting a predetermined amount of the liquid refrigerant to flow through said opening.

GEORGE W. JACKSON. 

